Purple pages of ancient New Testament manuscript were dyed with urine, new study reveals

Analysis of Codex Purpureus Rossanensis, by researchers at Italy’s Central Institute for Restoration and Conservation of Archival and Library Heritage (ICRCPAL), has revealed that its unique purple parchments were the result of treatment with a mixture of weeds and urine. Celebrated as one of the oldest extant illuminated manuscripts of the New Testament, the 1,500-year-old document was included in UNESCO’s Memory of the World Register last year.

According to the team, the unusual composition of the pages was uncovered during attempts to restore the sacred Byzantine text. Up until now, it was believed that Tyrian purple, a natural dye obtained from sea snails, was responsible for imparting the spectacular purple color to the parchment sheets. Recent research, however, indicates that it might have been brought about through the use of orcein, a type of dye extracted from the lichen species Roccella Tinctoria. To arrive at the unique color, the natural dye was processed using fermented urine, which back then was the only available source of ammonia.

Discovered in 1879 in the Cathedral of Rossano, an Italian town in the region of Calabria, the precious artifact recounts the story of Jesus, in accordance with the gospels of Mark and Matthew. Believed to have been created in Syria somewhere between the 5th and 6th centuries A.D., the text contains around 188 pages, featuring intricate miniatures and text written in Greek in silver and gold ink. Speaking about the Codex Purpureus Rossanensis, the spokesperson of the museum at Rossano, where the book is currently kept, said:

Most likely, what we have today represents half of the original book.

Experts are of the opinion that the New Testament manuscript, in its present condition, lacks two additional gospels, which might have been destroyed in a fire back in the 17th century. Over the last three years, the team at ICRCPAL has carried out an extensive restoration project, in an attempt to reverse damage afflicted during a previous restoration in 1917-19. To ensure proper preservation, the researchers did away with any kind of invasive procedures, including the process of stitching tears, cuts as well as small gaps on the codex. Instead, they examined the composition of the colors used in the book. Marina Bicchieri of ICRCPAL said:

Even though early medieval illuminated manuscripts have been deeply studied from the historical standpoint, they have been rarely fully described in their material composition.

According to Bicchieri, X-ray fluorescence pointed to the complete absence of bromine, a compound that is usually found in Tyrian purple. Following that, the team went about the task of preparing several natural dyes with the help of instructions present in the Stockholm papyrus, a 300 A.D. Greek manuscript contaning nearly 154 recipes of dyes and colors. Bicchieri explained:

Fiber optics reflectance spectra (FORS) showed a perfect match between the purple parchment of the codex and a dye obtained with orcein and an addition of sodium carbonate.

As the researchers point out, back in the day, sodium carbonate was likely sourced from natron, a mineral bearing similarities with table salt. The compound, according to Bicchieri, was widely used by ancient Egyptians during mummification, thanks to its powerful drying properties. Further analysis using Raman spectroscopy revealed that the some of the reddish mauve or violet shades used in the illustrations were acquired from an elderberry-based lake. Bicchieri added:

It is the first time that elderberry lake is found in such an ancient illuminated manuscript.

The research seems to dismiss previous claims that certain miniatures were not part of the original manuscript, and were added later in the 12th century. Such claims, however, are unfounded, since the illustrations were all made using the same color palette. The sacred book is currently housed inside a specially-designed humidity and temperature-controlled showcase in the Diocesean Museum of Rossano. A spokesperson at the museum was reported saying:

This codex has an extraordinary historical, artistic and religious significance. It is a symbol for a region like Calabria that reconciled eastern and western civilizations.